   (let [browser (get-current-browser (:db cofx))
         options (get-in cofx [:db :browser/options])
         current-url (:url options)]
-    (when (and (not (string/blank? url)) (not= "about:blank" url) (not= current-url url) (not= (str current-url "/") url))
+    (when (and browser (not (string/blank? url)) (not= "about:blank" url) (not= current-url url) (not= (str current-url "/") url))
       (let [resolved-ens (first (filter (fn [v]
                                           (not= (.indexOf ^js url (second v)) -1))
                                         (:resolved-ens options)))

  [cofx browser url]
  (let [history-index (:history-index browser)
        history       (:history browser)]
    (let [new-history (conj (subvec history 0 (inc history-index)) url)
          new-index   (dec (count new-history))]
      (update-browser cofx
                      (assoc browser
                             :history new-history
                             :history-index new-index)))))

(defmulti storage-gateway :namespace)


(fx/defn update-browser-name
  [cofx title]
  (let [browser (get-current-browser (:db cofx))]
    (when (and browser (not (:dapp? browser)) title (not (string/blank? title)))
      (update-browser cofx (assoc browser :name title)))))

(fx/defn navigation-state-changed
